House



(No Model.)

A. G. WATERHOUSE.

REGULATION OF. DYNAMO ELECTRIC MACHINES.

No. 389,030. Patented Sept. 4, 1888.

WITNESSES 14. mm,

M/VE/VTUH, 44 0406414, )y M A mm' H. PETERS. PhoPwLilhagupher, Waihmgtnn. n. C.

UNITED STATES PATENT OFFICFG ADDISON G. WATERHOUSE, OF HARTFORD, CONNECTICUT, ASSIGNOR TO THE WATERHOUSE ELECTRIC AND MANUFACTURING COMPANY, OF

SAME PLACE.

REGULATION OF DYNAMO -ELEGTRIC MACHINES.

SPECIFICATION forming part of Letters Patent No. 389,030, dated September 4, 1888.

Serial No. 269,641. (No model.)

To all whom it may concern.-

Be it known that I, ADDISON G. WATER- HOUSE, a citizen of the United States, and a IO rent generated by the machine is preserved constant,irrespective of any changes occurring within the machine itself or in the external circuit within which the machine is included.

In a former application filed by me on November 20, 1885, Serial No. 183,380, I have generally described the construction of a dynamo-electric machine and a method by which the machine is self-regulated.

My present invention is an improvement upon the construction and method set forth in the aforesaid application; and it consists of the combination, with a dynamo constructed as described, of a device responding to changes in the main current, and mechanism controlled by such responsive device, whereby the resistance of the circuit within which the machine is included may be automatically varied between the main positive brush and the point of connection of the auxiliary brush thereto, and a more perfect regulation of the machine thereby effected.

My invention further relates to the combination, with a machine constructed as described and the electro-responsive device, of

a supplemental hand-resistance which may be employed with or independently of the electro-responsive device for the purpose of adjusting the resistance interposed between the main positive brush and the point of connec- 4 tion of the auxiliary brush.

Myinvention also relates to the combination, with a machine constructed as described and with the eleetro-responsive device located as described, of a device responding to changes in the main current, whereby resistance may be cut into the shunt-circuit of said machine, for the purpose hereinafter set forth.

In my previous application I have stated that a machine constructed and balanced as described would be found to be practically self-regulating. In practice thisis true within limits; but it is found that the heat generated within the machine when in operation, and also various disturbances in the external cir cuit, tend, by changing the resistance of the several circuits on the machine or that of the external circuit, to destroy the balance, which is the condition for perfect regulation, and thereby necessitate a new adjustment to meetthe changed conditions.

The object of my present invention, therefore, is to provide a means for automatically making the new adjustments required-that is to say, to coact with the method of regulation described in my former application-end thus provide a means for maintaining a perfeet balance without human intervention.

In the accompanying drawings, which illustrate myinvention, similar letters of reference indicate like parts.

Figure 1 shows a machine in elevation provided with an auxiliary collecting-brush resting upon the commutator in advance of one of the main brushes and connected to the fieldcircnit of the machine, so as to include three of the magnets in what I term the field circuit. Fig. 2is a similar view showing two auxiliary brushes, one in advance of each of the main brushes and connected as in Fig. 1. Fig. 3 shows a machine connected as in Fig. 1, and also illustrates a hand and automatic resistance located in the field'circuit of said machine, a resistance in the shunt-circuit of said machine, and electro-responsive devices in the main circuit of said machine, which opcrate to cut resistance into or out of the several circuits as required.

In the diagrams, A indicates the armature of the dynamo, which may be either of the drum or ring type, and the helices thereon connected to the commutator B in the wellknown manner to form a closed circuit. To

insure sensitive action of the machine, the commutator B should have as great a number of plates and connections as are practicable in order to reduce the spark to the minimum and so as to take off the current from thearmature nearest to the diameter of commutation.

LII

G and D are respectively the and col lecting-brushes arranged opposite to each other and bearing normally upon the points of maximum and minimum currents of the commutator. The brushes 0 D are connected together by the conductor E, which is carried around the magnets F, F F and I5, connecting them in series and in series with the external resistancc.

G is an auxiliary brush, shown in the diagram as bearing upon the commutator in advance of the brush 0 and connected to the conductor E at I through the medium ofthe conductor H.

In Fig. 2 two auxiliary brushes, G G, are shown connected through the conductors H and H with the conductorE at I and I. The arrangement in Fig. 2 is merely a duplication of that of Fig. 1. I have shown this form in order to illustrate that whatever use can be made of one auxiliary brush-such as brush G as auxiliary to brush C-can also be applied to brush G as auxiliary to brush D. That portion of the circuit from brush O to G, including the armature-helices which ends at I, I term, for the purpose of description, the field-circuit, and from I to brush G the shunt-circuit.

The theoretical principle governing the op eration of a dynamo constructed and connected as shown in Figs. 1 and 2 has been fully set forth in my former application, and it is not necessary to repeat it at length in this specification.

Referring now to Fig. 3, K indicates an electro-Inagnet included in the external circuit, E,

of the machine. IVithin the magnet is the core L, provided with the extension L, extending through the solenoid and adapted to strike on the bottom of the box L when the core falls by gravity by reason of there being no current in the circuit E. Interposed in the conductor E is the changeable resistance M, formed of a number ofindependent coils connected together in the usual manner and to the plates N N N, the upper ends of which form an areshaped surface. Resting upon this surface is the rocker 0, connected through the rod P with the armature L of the solenoid K. The rocker O is connected through the conductor E with the resistance-coils of the hand-resistance Q, which in turn is connected through the conductor E with the conductor E, which passes around the magnet F, and from thence to the external circuit, E.

R represents an electro-magnet in the wire E, and Sis a high resistance interposed in the shuntconductor H, of such an amount as to practically prevent the current from the brush 0 from passing back over the wire H, and thus short-circuiting the machine.

In the conductor H which forms a by-path around the resistance S, is an armature, T, pivoted at a, and adapted to be actuated by the magnet B when excited and raised until its end strikes the contact-point X, which is conncoted to the wire H This by-path when the machineis at rest is open, but closed when the machine is in motion.

The operation of my device is as follows: The current collected from the auxiliary brush, as I have set forth in my former application, serves to increase or diminish the current transmitted through the fieldcircuit ofthe machine, and thus regulate the current to the external resistance, by reason of the variation of the current from brush G, due to the variation in the electro motive force at said brush, due to the shifting of the diameter of commutation as effected by the external resistance of the circuit within which the machine is included.

The operation of the device by which the resistance is cut into the field-circuit is as follows: WVith the machine at full load, the core L of the solenoid K is at its lowest point, and hence the rocker O rests upon the contactplate N of the changeable resistance'coil. WVith any change in the external circuit by which the resistance of the circuit is decreased, or any change in the machine itself by which the current transmitted to the external circuit is greater than a predetermined amount, then the magnet K attracts its armature, lifting it upward and rotating the rocker so as to include more of the resistance-coil, say to the point N. The movement of the core of the solenoid will of course continue until its limit of motion is reached or the resistance cut into the circuit is sufficient in amount to reduce the current in the external circuit to the normal amount. In other words, through the instrumentality of this device I am enabled to preserve the relative resistance or balance between the shunt, the field-circuit of the machine, and the external circuit within which the machine is included.

The hand-resistance Q (shown in the drawings) is connected in circuit with the automatic resistance, and is merely supplemental thereto and convenient for use in starting the machine. It may be used with the automatic resistance, or independently thereof. Vhen the machine is first startcd,an adjustment may be obtained through the hand-resistance, which will serve until the automatic resistance is brought into action. In the shunt-circuit I have shown a high resistance, and also a path around this resistance within which is located a device by which this path maybe opened or closed. By reason of this arrangement the current is normally transmitted through the path of low resistance and acts automatically. Should the main circuit be broken, the electromagnet releases the armature, and thus opens the path of low resistance and diverts the current through the path of high resistance, so as to prevent the transmission of a local current in the circuit formed from brush 0 around the field-magnets to a j unction, I, and back through the low-resistance shunt to brush G, and the coils of the armature interposed between the brushes 0 and G. The second function of this arrangement is that sometimes the balance re quired between the shunt, field, and external circuit, in order to produce self-regulation and maintain a proper current, requires the shuntcircuit to be of such small resistance that at first the machine will not start. I therefore leave the low-resistance path of the shunt circuit normally open until it is closed by the infinence of the main current. In all cases I have shown the junction of the shuntcircuit at I between the field-magnets F and E; but the same may be connected at any point of the circuit within which the machine is included. I have described the adjusting resistance as always interposed in the field-circuit. It will be obvious that the same method of regulation may be applied to the shunt-circuit. I prefer, however, to effect the regulation in the fieldcircuit, as, by reason of the difference in current in the two circuits, the changes required to effect the balance are much smaller in the field-circuit and the action much more sensitive than is the case where the regulation is effected in the shunt-circuit.

I claim as my invention 1. The herein-described method of regulating the current from a dynamo-electric ma chine, which consists in collecting the current in two portions, shunting one portion of said current around one or more of the field-magnet coils, and in varying the resistance of the circuit in which said shunted coils are included, substantially as described.

2. The herein-described method of regulating the current from a dynamo electric machine,which consists in collecting the current in two portions, shunting one portion of said current around one or more of the field-magnet coils, and in varying the resistance in the shunt-circuit, substantially as described.

3. The herein-described method of regulating the current from a dynamo-electric ma chine, which consists in collecting the current in two portions, shunting one portion of said current around one or more of the field-magnet coils, and in varying the resistance of the circuit in which said shunted coils are included and that of the shunt-circuit simultaneously or separately, substantially as described.

In witness whereof I have hereunto set my hand this 21st day of March, 1888.

ADDISON G. \VATERHOUSE.

lVitnesses:

SAMUEL O. PRENTICE, CHAS. E. CHAPIN. 

